Tetrakisazo dye.



. STA

WILHELM HERZBERC-r,

Es PATENT oFFIoE.

F SCI-ItjNEBERG, NEAR BERLIN, AND WERNER LANGIEL OF TREPTOW, NEAR BERLIN, GERMANY, ASSIGNORS TO ACTIEN GESELLSCHAFT Fill? ANILIN EABRIKATION, OF BERLIN GERMANY.

TETRAKISAZO' DYE.

997,061. No Drawing.

Patented July 4, 1911. 1911. Serial No. 615,408.

To all whom it may concern:

Be it known that we, \VILHELM Hnnznnno and WERNER Larson, subjects of the German Emperor, residing, respectively, at Schiineberg, near Berlin, and Treptow, near Berlin, Germany, our post-otlice addresses being, respectively, Laiulshuterstrasse 2a, Schtineberg, near Berlin and Bouchstrasse 1-1, Treptow, near Berlin, Germany, have invented certain new and useful Improvements in Tetrakisazo Dye, of which the following is a specification.

()ur invention relates to the manufacture of valuable dyes for cotton, which may be obtained by combining with two molecular proportions of a meta-diamin of the benzene series one molecular proportion of a tetrazotized dye made from two molecular propo'i'tions of a diazotized amino-acid and one molecular proportion of a symmetrical 3.3-

. diaminodiaryl-urea of the benzene series.-

I The tetrakisazo dyes thus manufactured pro-' duce on cotton directly red-brown tints, which by subsequent treatment with tnitrodiazobenzene become deep red-brown of excellent tastncss to washing and to light.

The following example serves to illustrate our invention, the parts being by weight: 17.3 parts of metanilie acid are diazotizcd and mixed with 12 parts of symmetrical 3.2% diaminodiphcnyl-urea, dissolved in 10 parts of hydrochloric acid of "20 Baum specific gravity and parts of water. The combination begins immediately and is completed by introducing sodium acetate until free bydrochloric acid has disappeared. 25- parts-- of hydrochloric acid are now added, the mixture is tetrazotized by means of 7 parts of sodium nitrite and the tetrazo solution is run into a solution of 11 parts of metaphenylenediamin, made alkaline with sodium carbonate. \Vhen the combination is completed the dye is salted out hot and drained. It dyes cotton directly red-brown tints, which by subsequent treatment with L nitrodiazobenzene become a powerful redbrown.

The new tetrakis-azo dye as above obtained, which is in the dry shape a brownishblack powder, dissolves in water to a brown solution which on the addition of soda-lye assumes a little more reddish'brown color, whereas by the addition of sulfuric acid brown flakes are separated. in concentrated sulfuric acid it dissolves to a blue-solution;- on the addition of ice at first the color turns to violet, then brown flakes are separated. The aqueous solution of the dye is decolorized by the addition of stannous chlorid and hydrochloric acid, the dye thus being split up, yielding mctanilic acid, triaminobenzenc and symmetrical 2.5,2. nylurea.

It is obvious to those skilled in the art that our present invention is not limited to the foregoing example or to the details given therein. It may be stated that instead of metanilic acid'otlier amino-acids, instead of 3.2%diaminodiphenylurea other. 3.3-diaminodiarylurca-s of the benzene series, such as the homologues and other substitution roducts of the said diaminodiphenylurea, adapt.- ed for combining with diazo compounds may be used. For the phenylenediamin toluylenediamin and chlorophenylenediamin may be substituted.

Having now described the invention and the manner in which it may be performed what we claim is,-

1. As new articles of manufacture the hereinbefore-described new tetrakis-azo dyes which may be obtained by combinin with two molecular proportions of a metaiamin of the benzene series one'molecular proportion of a tetrazotized dye made from two molecular proportions of a diazotized aminoacid and one molecular proportion of a symmetrical 3.3-diaminodiaryl-urea of the benz'ene serics,these new dyes prod ucing on cotton directly I'GClzbI'OWH tlnts, winch by subsequent treatment with 4-nitrodiazobenzene become deep brown, which new dyes when pulverized are brownish-black powders soluble in water to brown solutions, which n the addition of a mineral acid separate the free acids of the dyes, and which dyes are soluble in concentrated sulfuric acid to blue solutions, on the addition of ice at first turnin to violet solutions, whereupon the free acids of the dyes separate, winch dyes by reduction yield the ammo acids employed as starting mate rial besides symmetrical 2.5,9..5-tetraminodiarylureaot' the. benzene series and 1.2.4- triamins of the benzene series.

2. As a new article of manufacture the herein-described new tetrakis-azo dye which may be obtained by combining with two molecular proportions of phenylenediamin on the addition of a mineral acid separates the free acid of the dye and which dye is soluble in concentrated sulfuric acid to a blue solution, on the addition of ice at first turning to a violet solution, whereupon the 5 free acid of the dye separates, which dye by reduction yields nietanilic acid besides symmetrical 2.5,2.5-tetraminodiphenylurea and LQA-triaminobenzene.

In testimony whereof we have hereunto 20 set our hands in presence of two subscribing witnesses.

WILHELM HER-ZBERG. WERNER LANGE.

\Vitnesses WOLDEMAR HAUPT, HENRY HASPER. 

